The present work aims to design and synthesize novel series of spiro pyrazole-3,3’-oxindoles analogues and investigate their bioactivity as antioxidant and antimicrobial agents, as well as antiproliferative potency against selected human cancerous cell lines (i.e., breast, MCF-7; colon, HCT-116 and liver, HepG-2) relative to healthy noncancerous control skin fibroblast cells (BJ-1). The mechanism of their cytotoxic activity has been also examined by immunoassaying the levels of key anti- and proapoptotic protein markers. The analytical and spectral data of the all synthesized target congeners were compatible with their structures. Synthesized compounds showed diverse moderate to powerful antimicrobial and antioxidant activities. Results of MTT assay revealed that seven synthesized compounds (i.e., 11a, 11b, 12a, 12b, 13b, 13c and 13h) particularly exhibited significant cytotoxicity against the three cancerous cell lines under investigation. Ranges of IC50 values obtained were 5.7–21.3 and 5.8–37.4 µg/mL against HCT-116 and MCF-7, respectively; which is 3.8 and 6.5-fold (based on the least IC50 values) more significant relative to the reference chemotherapeutic drug doxorubicin. In HepG-2 cells, the analogue 13h exhibited the highest cytotoxicity with IC50 value of 19.2µg/mL relative to doxorubicin (IC50 = 21.6µg/mL). The observed cytotoxicity was specific to cancerous cells, as evidenced by the minimal toxicity in the noncancerous control skin-fibroblast cells. ELISA results indicated that the observed antiproliferative effect against examined cancer cell lines is mediated via engaging the activation of apoptosis as illustrated by the significant increase in proapoptotic protein markers (p53, bax and caspase-3) and reduction in the antiapoptotic marker bcl-2. Taken together, results of the present study emphasize the potential of spiro pyrazole-oxindole analogues as valuable candidate anticancer agents against human cancer cells.
本研究旨在设计和合成新型的螺环吡唑-3,3'-氧化吲哚类似物系列,并研究它们作为抗氧化剂和抗微生物剂的生物活性,以及相对于健康的非癌细胞控制皮肤成纤维细胞(BJ-1)对选定的人类癌细胞系(即乳腺癌MCF-7、结肠癌HCT-116和肝癌HepG-2)的抗增殖效力。通过免疫测定关键的抗凋亡和促凋亡蛋白标记物水平,也对它们的细胞毒活性机制进行了研究。所有合成目标同系物的分析和光谱数据与它们的结构相符。合成的化合物表现出多样的中等至强大的抗微生物和抗氧化活性。MTT实验结果显示,七种合成的化合物(即11a、11b、12a、12b、13b、13c和13h)特别对所研究的三种癌细胞系表现出显著的细胞毒性。获得的IC50值范围分别为5.7-21.3和5.8-37.4µg/mL,相对于健康的非癌化疗药物多柔比星,这分别是3.8和6.5倍(基于最小IC50值)更显著的。在HepG-2细胞中,类似物13h表现出最高的细胞毒性,IC50值为19.2µg/mL,相对于多柔比星(IC50=21.6µg/mL)。观察到的细胞毒性是特异性的,证明在非癌细胞控制皮肤成纤维细胞中毒性极小。ELISA结果表明,针对检测的癌细胞系的观察到的抗增殖效果是通过促进凋亡的激活介导的,如显著增加的促凋亡蛋白标记物(p53、bax和caspase-3)和减少的抗凋亡标记物bcl-2所示。综合以上结果,本研究结果强调了螺环吡唑-氧化吲哚类似物作为针对人类癌细胞的有价值的候选抗癌剂的潜力。